First the disclaimer - I am involved in politics, and a member of the Labour Party, as well as a trade union member (not of unite)
Unite the union is an amalgamation of a number of different trade Unions that have merged over time.
They and other unions such as my own (Unison) have a long history of political activity, and as such unions were the foundation on which the Labour Party was built over 100 years ago. This remains true today, and unions have a great deal of interaction with the party.
Unite renewed their political strategy in 2011, which reinforced the commitment to work with the Labour Party.
Ukip as a political party remains without any influence in the uk parliament having no elected ministers, however they are hoping to cash in on the success they had in the recent European elections, when the uk has a general election next year 2015.
They are a right wing party with policies that would reduce workers rights.
It is because of this type of policy opinions that unite would never consider moving its affiliations to a party such as ukip.
It is also part of Unions Together, a cross union campaign group, which is actively campaigning against ukip
With regards to globalisation, unions in the uk are currently opposing an Eu Us trade deal that they think will do harm to public services in the uk
Unions are there to support members, and will campaign about things that would damage the pay and conditions of their members, as such unions are not intrinsically anti globalisation, but they would campaign against something that would be to the detriment of members, such as the eu us deal I mentioned earlier